Lunar Eclipse Photography - Dan L. Ward with data for January 20-21, 2019 - Northern Virginia Astronomy Club

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Lunar Eclipse Photography - Dan L. Ward with data for January 20-21, 2019 - Northern Virginia Astronomy Club
Lunar Eclipse Photography
   with data for January 20-21, 2019

                        Dan L. Ward
                        photos@danlward.com
Lunar Eclipse Photography - Dan L. Ward with data for January 20-21, 2019 - Northern Virginia Astronomy Club
Nasim Mansurov
                       https://photographylife.com/how-to-photograph-a-lunar-eclipse

Lunar eclipses offer                                                                   This image took 18
  a beautiful, but                                                                      exposures over a
 challenging photo                                                                     three hour period.
    opportunity
Lunar Eclipse Photography - Dan L. Ward with data for January 20-21, 2019 - Northern Virginia Astronomy Club
Background Terms
• Lunar eclipses occur when the Moon moves through the Earth’s
  shadow
• The shadow has an outer lighter fringe area – the Penumbra,
  and an inner dark core area – the Umbra
• The Penumbral stage is barely noticeable
• The Umbral stage is darker and obvious
• Most lunar eclipse photos are from the Umbral stages
• The brightness of an eclipse primarily depends on how deeply it
  goes into the shadow and the transparency of the Earth’s
  atmosphere
• Reaching perigee on Jan 21, this will be a “supermoon” eclipse
Lunar Eclipse Photography - Dan L. Ward with data for January 20-21, 2019 - Northern Virginia Astronomy Club
Supermoon vs Micromoon
  http://www.perseus.gr/Astro-Lunar-Scenes-Apo-Perigee.htm
Lunar Eclipse Photography - Dan L. Ward with data for January 20-21, 2019 - Northern Virginia Astronomy Club
Danjon Scale - Lunar Eclipse Brightness
Danjon Value   Description
   L=0         Very dark eclipse. Moon almost invisible, especially at
               mid-totality.

   L=1         Dark Eclipse, gray or brownish in coloration. Details
               distinguishable only with difficulty.

   L=2         Deep red or rust-colored eclipse. Very dark central
               shadow, while outer edge of umbra is relatively bright.

   L=3         Brick-red eclipse. Umbral shadow usually has a bright
               or yellow rim.

   L=4         Very bright copper-red or orange eclipse. Umbral shadow
               has a bluish, very bright rim.

                https://www.unc.edu/~rowlett/units/scales/danjon.html
Lunar Eclipse Photography - Dan L. Ward with data for January 20-21, 2019 - Northern Virginia Astronomy Club
Penumbral eclipse
                                                           Oct 18, 2013

                                                                             Dan Ward photo
                                                                  1000mm f/8.3 (telescope) 1/400 ISO 100
https://en.wikipedia.org/wiki/October_2013_lunar_eclipse

                            The Penumbral phase is subtle and hard to detect visually.
                                The Umbral phase offers more striking exposures.
Lunar Eclipse Photography - Dan L. Ward with data for January 20-21, 2019 - Northern Virginia Astronomy Club
Lunar Eclipse Photography - Dan L. Ward with data for January 20-21, 2019 - Northern Virginia Astronomy Club
Moon Altitude/Azimuth Table
                                       January 20-21 2019
       EST                         Altitude                         Azimuth                         Stage
     21:37                              51                               106                           P1
     22:35                              61                               122                           U1
     23:42                              69                               153                           U2
     00:13                              71                               173                          Mid
     00:44                              70                               195                           U3
     01:52                              63                               230                           U4
     02:49                              54                               248                           P4
   Altitude = apparent degrees above the horizon.                              Calculated from the US Naval Observatory site:
0 = horizon. 90 = overhead. A closed fist at arms length is 10 degrees         http://aa.usno.navy.mil/data/docs/AltAz.php
              Azimuth = Compass Directions.
         0 = North, 90 = East, 135 = Southeast, 180 = South
Lunar Eclipse Photography - Dan L. Ward with data for January 20-21, 2019 - Northern Virginia Astronomy Club
Dan Ward - partial eclipse Oct 8, 2014
                                                 Image Scale

Lens      Format       Horizontal        Vertical      Diagonal
                                                                                         As shot
24
            FX           73.7            53.1          84.1
mm
                                                                  Dan Ward: 300mm f/11 1/250 ISO 320
           DX            52.0            36.0          60.7
120
            FX           17.1            11.4          20.4
mm
           DX            11.1             7.4          13.4
300
            FX            6.9             4.6           8.2
mm
           DX             4.5             3.0           5.4
                                                                                            Cropped
   http://www.nikonians.org/reviews?alias=fov-tables
Lunar Eclipse Photography - Dan L. Ward with data for January 20-21, 2019 - Northern Virginia Astronomy Club
Adjusting for Exposure
• The range of “correct” exposure settings will vary
• Daylight white balance (or shoot raw)
• Depth of field is irrelevant at 240,000 miles
• Sharpest moon images typically are f/5.6, f/8 or f/11
• ISO 100, f/11, 1/250 is a typical full moon setting
• Manually Focus, verify, then lock it (use tape)
• Blur is caused by focus, camera movement, mount vibration,
  shutter vibration, mirror slap, dew, relative moon motion, etc.
• Variations in eclipse brightness
    –   Measured using the Danjon scale (0 – 4)
    –   Depth of Umbra is key
    –   Earth’s atmospheric conditions contribute
    –   Orbital position (apogee, perigee) contributes
• Eclipse exposure typically vary from 8 to 12 stops
Nasim Mansurov

   https://photographylife.com/how-to-photograph-a-lunar-eclipse
Eclipse with Milky Way
 50mm f/1.8 10 min ISO400
Getting the Best Moon Focus
•   Use the optimal F/stop for your lens
•   Typically – f/5.6, f/8 or f/11
•   Depth of field is irrelevant at 248,000 miles!
•   Focusing Technique Suggestion
     – Auto Focus first on edge (optional)
     – Switch to manual focus
     – A focusing mask can help fine tune
     – Use a focusing lever for micro tweaking
     – At best focus, lock in place with tape
     – Recheck focus periodically
     – Use the lowest ISO with an acceptable shutter speed
Camera Focusing Options
Optional Focusing – DSLR
•   Use ‘Live View’
•   Aim camera at the moon
•   Manual focus
•   Use ‘magnify’ button to enlarge image on
    screen
    – Fine tune focus
    – Apply masking tape carefully
Focusing Masks
The Hartmann Mask is simply a set of
holes in an opaque material. The one
in the photo is made out of cardboard.
Like a split level focuser on
rangefinders, you adjust the focus until
the images merge into one. Two hole
versions, called Scheiner discs, are the
most common, but there are variations
in the number of holes and shapes.

                                                             The Bahtinov mask is a more
                                                             sophisticated version of this type of
                                                             mask. They use a series of slots to
                                                             create unique diffraction patterns and
                                                             you achieve focus by centering the
                                                             spikes. This type of mask is very
                                                             popular with ccd imagers.

                                                                   http://www.kendrickastro.com/kwikfocus.html
http://www.astropix.com/HTML/I_ASTROP/FOCUS/METHODS.HTM#HM
Reducing Moon Photo Blur
•   Use a Sturdy tripod
•   Hang extra Weight on the tripod
•   Use Vibration Pads (mouse pads work)
•   Use a wireless or wired Remote Shutter or Timer
•   Use Mirror Lock if your camera has it
•   Check for Dewing on the lens periodically
To Avoid Blur from the Moon’s Motion
• Divide focal length into 400 for fastest shutter speed
    (e.g. 400/200mm = 2 seconds, 400/300mm = 1.3 seconds)
• For longer exposures, use a tracking motor
• Use lunar rate, not sidereal
• Lunar movement is also 12% faster at Perigee
Eclipse Nonet – April 15, 2014
            2 X 770mm f/12 1/400 to 8 seconds, ISO 400
    http://www.mreclipse.com/LEphoto/TLE2014Apr/TLE2014Apr-nonet1.html
Getting the Right Exposure
Lunar eclipses may vary 12+ stops in brightness
Have a strategy for adjusting your exposures
• Trade off between Shutter, Aperture and ISO
• Bracket exposures for insurance
• Suggested Priorities:
  –   Fix focus early in the eclipse
  –   Limit the aperture range changes
  –   Change the ISO as required for dimness
  –   Know the shutter minimums for moon motion
Useful Website Links:
Nasim Mansurov:        https://photographylife.com/how-to-photograph-a-lunar-eclipse

Nasim Mansurov:        https://photographylife.com/how-to-photograph-moon

Marie Joabar:          http://capitalphotographycenter.com/blog/article/how-to-shoot-the-moon

Peter West Carey:      http://photography.tutsplus.com/articles/the-basics-of-better-moon-photography--photo-10455

Matt Quinn:            http://petapixel.com/2014/10/15/part-1-how-to-photograph-the-moon/

Fred Espenak:          http://www.mreclipse.com/

US Naval Observatory: http://aa.usno.navy.mil/data/docs/AltAz.php

    Astronomy Clubs:
NOVAC:                 http://www.novac.com/wp/ (Northern Virginia)

ATMOB:                 http://www.atmob.org/                    (Boston area)
Phillip Cruden – Blood Moon Mosaic
    http://optas.net/april-14th-15th-2014-lunar-eclipse-blood-moon-mosaic/#.VfTst7TN_M4

                                                                                          Good luck &
                                                                                          avoid clouds!
Ken Butler’s Eclipse Sequence
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